There are pantoscopic cameras which are known as stereoscopic cameras having two photo receivers (image pickup units) with respective optical axes at different positions. When an image is picked up through such a stereoscopic camera, right and left images corresponding to a parallax caused when an image is viewed with naked eyes can be obtained. Accordingly, the stereoscopic cameras are used for generating a stereoscopic image (three-dimensional image).
As explained above, a stereoscopic camera has two photo receivers (image pickup units), and when, in particular, such a stereoscopic camera is realized by a compact camera, as a finder image displayed on a rear display panel or an electronic view finder, an image picked up by either one of the image pickup units is often used. In this case, if there is an obstacle nonrelated to the purpose of image pickup, e.g., a finger of a person using the camera which contacts a lens face within an image pickup range where the image pickup unit picks up an image not for the finder, such an obstacle does not appear on the finder image. As a result, a person using the camera does not notice the unexpected appearance of the obstacle, thereby failing to pick up a necessary image or needing to pick up an image again.